Heat the oven to 180C / 160C fan / gas mark 4.
Line a small-to-medium sized tin with parchment paper – we used a 20 x 10cm loaf tin as that was what we had handy. A square tin or tray bake tin will do, although the final product might not be as thick.
Melt the butter in a bowl over a pot of bubbling but not boiling water.
Once the butter has melted, remove from the heat and beat in the sugar.
Leave the bowl to cool.
Once the bowl has cooled to room temperature, add in your beaten eggs.
Fold in the flour and matcha – just 1 tablespoon, as a little goes a long way.
Stir through chunks of white chocolate. We used chocolate buttons for ease.
Bake for 25 mins.
The blondies will still be a little soft to touch. That’s fine, as they will harden at room temperature, but do pierce them with a skewer to check that they're fully cooked inside. The skewer should come out clean, with nothing stuck to it.
Leave to cool and cut into squares to serve.